SAN JOSE, Costa Rica – An American senior citizen killed an alleged mugger with his bare hands, and his travelling companions aboard a tour bus fended off two other assailants in the Atlantic coast city of Limon, police said.

The American, who is about 70 years old and retired from the military, put the 20-year-old in a head lock and broke his clavicle after the suspect and two other men armed with a knife and gun held up their tour bus, said Luis Hernandez, the police chief of Limon, 80 miles east of San Jose. The suspect, Warner Segura, was later declared dead, apparently from asphyxiation.

The two other men fled when the 12 senior citizens started defending themselves during the Wednesday attack. Afterward, the tourists drove Segura to the Red Cross where he was declared dead. The Red Cross also treated one of the tourists for an anxiety attack, Hernandez said Thursday.

The tourists left on their Carnival cruise ship after the incident and Hernandez said authorities do not plan to press charges against them.

"They were in their right to defend themselves after being held up," he said.

Hernandez said Segura had previous charges against him for assaults.

In a media statement, Miami, Fla.-based Carnival Cruise Lines said the attack occurred during an outing that a group of a dozen passengers had arranged on their own at a Limon beach.

"According to witnesses, while sightseeing at a local beach, the group of guests were approached by three assailants, one of whom was armed," the statement said.

"The victims struggled with the armed perpetrator, and were able to disarm him. During this process, the gunman's two accomplices fled the scene. In the course of disarming and restraining the assailant, he died from apparent asphyxiation."

Neither the Costa Rican police nor Carnival identified the man involved in the struggle with the mugger.

The cruise line said the guests were questioned by local law enforcement and then returned to the ship. The ship's departure from Limon was slightly delayed.

"All of the guests involved, who had booked the cruise together as a group, have opted to continue with their vacation plans. Carnival is providing full support and assistance to the guests,'' according to the statement.

The ship, The Carnival Liberty, continued on its scheduled itinerary, with a port call scheduled in Colon, Panama.